Mid Mustard Khaki vs Sandstorm

How close are they?

ΔE 16.7, loose: different enough that you should pick on purpose. Sandstorm is noticeably lighter, more saturated, warmer than Mid Mustard Khaki.

Can I use Sandstorm instead of Mid Mustard Khaki?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Sandstorm is noticeably lighter, more saturated, warmer than Mid Mustard Khaki.

Can I use Mid Mustard Khaki instead of Sandstorm?

The same difference applies the other way round: Mid Mustard Khaki is noticeably darker, more muted, cooler.

ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.